Stanford Device Advancing Superconductivity Studies Reported

Stanford University scientists have made an electronic device of new superconducting substances, a breakthrough that could speed the development of superfast computers, scientists at Stanford University say.

The announcement is the most recent in a series of breakthroughs around the country on superconductivity, the transmission of electricity without resistance.

It addresses a key issue--the temperature at which scientists can use superconductive circuits, which are extremely fast electronic links. Until recently, superconductivity could be performed only at extremely cold temperatures; recently, laboratories in Switzerland, China and the United States developed materials that work at higher temperatures.

Stanford University's applied physics department announced that it had shaped those materials into thin films to create prototype electronic devices. The Stanford scientists, headed by Theodore H. Geballe, said they made superconducting films that are just 1,000 to 2,000 atoms thick by condensing a vapor of lanthanum strontium copper oxide onto a flat surface.

Geballe said the group has also produced two simple electronic devices, called point-contact junctions and sandwich-type tunnel junctions, with the substance and a somewhat similar yttrium barium copper oxide.

"It behaves even better than we hoped," said Geballe.

The Stanford group made the announcement in advance of a meeting on Wednesday of the American Physical Society in New York.

Malcolm Beasley, a team member, said one potential application would be to use the new superconducting materials as interconnections in semiconductor computers cooled with liquid nitrogen. Nitrogen changes from a liquid to a gas at about minus 320 degrees Fahrenheit.

High-temperature superconducting of a new group of materials was first reported by the International Business Machines research laboratory in Switzerland last spring.